Fans went crazy over Maren Morris' body and style in her epic shoot for Playboy, which debuted in June, but celebrity physical trainer Erin Oprea was focused on something else.

“I was like, ‘Maren, where the heck do you buy a Playboy these days?" Oprea says, laughing as she recalls asking the "Girl" hitmaker about the shoot. “I had never even bought a Playboy before.”

But as the woman who had a hand in helping Morris find her true potential both physically and mentally in recent years, Oprea had to see the layout for herself. "Maren is a strong lady,” the star trainer tells ToC. "It was such a classy layout. I thought it was well done and she looked beautiful."

“The other day we were doing a workout and Jana was squatting and putting a load in the washer and then squatting as she put it in the dryer," Oprea reveals of Kramer, who gave birth to son Jace earlier this year. "Sometimes the kids are with us so sometimes she holds the baby and sometimes I hold the baby [Laughs]."

Post-baby workouts can be filled with a whole slew of emotions, whether one is a celebrity or not. “I feel like that when everyone has a baby, they are excited and then the realness sets in and they start looking at their body and I’m always there to say it's okay,” Oprea says. “I remind them that they are perfectly imperfect and that we are going to work on being the best you possible. We are going to enjoy the journey together. It's slow and steady — it's not a crash course.”

And for the record, it's not easy, either!

"I see the worst of the worst in everybody," admits Oprea, who has also trainedUnderwood in the past. “We drop the excuses when we find the results. If it was easy, everyone would do it. No matter how negative somebody is, my goal at the end of the session is for them to feel better both physically and mentally. We are going to cry and then we are going to squat.”

When all is said and done, Oprea hopes she can help her clients discover an inner confidence that money can’t buy:

"When I can see them walk on a red carpet, whether they feel their best physically or not, I want them to walk that red carpet feeling beautiful, both inside and out."